From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [Patch 2 of 2]: PV-domain SMP performance Linux-part
Date: Fri, 19 Dec 2008 09:56:00 +0000
Message-ID: <C5712030.206AD%keir.fraser@eu.citrix.com>
References: <494B686F.1050505@fujitsu-siemens.com>
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To: Juergen Gross <juergen.gross@fujitsu-siemens.com>
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On 19/12/2008 09:25, "Juergen Gross" <juergen.gross@fujitsu-siemens.com>
wrote:

>> I haven't seen any win on any real world setup. So I remain unconvinced, and
>> it'll need more than you alone championing the patch to get it in. There
>> have been no other general comments so far (Jan's have been about specific
>> details).
> 
> Okay, would the following scenario be "real world" enough?
> 
> Multiple domUs being busy leading to enough vcpu scheduling, several parallel
> kernel builds in dom0 acting as benchmark.

Something like that would be better. Of course you'd need to measure work
done in the domUs as well, as one of the critical factors for this patch
would be how it affects fairness. It's one reason I'm leery of this patch --
our scheduler is unpredictable enough as it is without giving domains
another lever to pull!

 -- Keir